Curator Fred Mann in front of Annelies Strba's controverseial picture of her daughter in the bath. Photo: Sean Smith

Since the morning in 1859 when the bachelor don who wrote under the name of Lewis Carroll opened the shutter of his camera in front of six-year-old Alice Liddell, the neck of her beggar maid costume torn provocatively off the shoulder, artists with an interest in little girls have been guilty until proven innocent.

Last night a new moral uproar was brewing after a gallery owner was threatened with arrest for showing a picture of a girl in a bath taken by her artist mother after a passerby complained to the police that it was "paedophiliac and offensive".

The picture of Sonja Strba, taken 17 years ago in her Swiss home when she was 12, has already been published in a book and shown in several major European galleries without complaint. But last night Scotland Yard said that a file was being sent to the crown prosecution service who would decide whether the Rhodes + Mann gallery in east London should be prosecuted.

They are also looking at invites the gallery sent out for a private view of her mother Annelies Strba's show, 2,000 of which carried the offending photograph of Sonja lying red-eyed in the suds. Detectives also scrutinised two other photographs in the exhibition, one of her son Samuel in his underwear in bed and Strba's grandson playing naked in a flower bed. Neither seemed to perturb them.

The case has unsettling echoes of the furore 18 months ago when police threatened to seize three of American photographer Tierney Gearon's images of her children in the nude from the Saatchi Gallery in London. Then the former culture minister Chris Smith intervened to chastise officers for overstepping the mark between probity and censorship.

Like Gearon, Strba's work revolves around her photographing her family over the decades, sometimes in the nude but more often not, and if anything her work is more highly rated. Her deceptively artless snapshots of family life and more complex video meditations on ageing have been bought by the National Galleries of Scotland in Edinburgh and also hang in Leeds City art gallery. Strba, 55, has also been part of big group shows at the Hayward, Whitechapel and Photographers' galleries in London and is about to be the subject of a major retrospective in her native Switzerland.

In a week when Edinburgh parents were banned from photographing their children's nativity plays unless they had the permission of all the other mothers and fathers, this latest clash between public queasiness and artistic freedom has a morbid familiarity about it.

Lunacy

Fred Mann, the owner of the Shoreditch gallery now under investigation, said it was "lunacy to pick on Strba. I just don't understand it. Annelies Strba is an eminent artist whose work has been bought by public collections in museums from here to Timbuktu. She is not someone setting out for controversy, nor were we. Her work does contain photographs of children but they are not pornographic.

"I was told to prepare myself to be arrested after the police called. They were put on to us by the local paper after a woman complained to them. The police asked me whether I would take the picture down and I said I would not. This exhibition has been curated very carefully. When we were putting this exhibition together, the last thing that had occurred to us was that there would be any kind of scandal," he added.

Frith Street Galleries, who represent the artist in this country, were equally outraged. "Really this is just more of the same nonsense that the Saatchi gallery had to put up with. Strba's work has been exhibited without difficulty all over the world," said spokeswoman Kirsten Dunne.

The furore began when a mother of an 11-year-old boy complained to the Hackney Gazette about the photograph, which she saw from outside the glass-fronted gallery. This is not the first time that the culture of the area's working-class residents has clashed the newly arrived "arty set" who are pricing them out. Two years ago there was a similar ruckus over an exhibition of nudes in the nearby 291 Gallery. There are now more than 80 art galleries in the East End of London, cheek by jowl with some of the country's poorest and most conservative communities. On the lower part of Hackney Road where the Rhodes + Mann gallery is situated, cutting-edge galleries compete with evangelical African churches for passing trade.

Nik O'Flynn, editor of the Hackney Gazette, said the woman's objections were based on the fact that the photograph was visible from the street. "She felt it was an encouragement to the dirty mac brigade. It was that it was in her face that really made her angry."

Artist Jake Chapman, who with his brother Dinos has toyed with the bounds of taste in shows like Sensation, said indecency was in the eye of the beholder. "There is a very strange atmosphere about at the moment. Dinos was stopped from taking pictures of his child in a swimming pool the other day and asked for his name and address in case he was a paedophile."

But if artists wanted to play with social mores, he argued, they must expect to suffer a backlash now and again. "If you poke fun at other people's cultural values, you deserve what you get. You can't expect an open licence from everyone.

"I don't want to be on the side of the police, but it is good in some ways because it challenges this smug art world complacency, that its values are untouchable by other value systems."

A Scotland Yard spokeswoman said officers would be consulting the CPS to establish whether displaying the photograph breaks any laws. "Police have taken copies of the photograph and are seeking advice as to whether it contravenes the Obscene Publications Act," she said.

CURIOUSER AND CURIOUSER - ALICE AND OTHER MUSES

· Balthazar Klossowski, better known as Balthus, arguably the last great figurative painter of the 20th century, was infamous for his portraits of adolescents. His pictures of naked or partly clothed girls hitching up their skirts to reveal their knickers slowly began to erode his reputation, so much so that by his death last year he was almost as well known as a supposed "pervert" as a painter.

·Degas's wax sculpture, The Little Dancer 14 Years Old, was once the subject of heated argument as to the artist's degenerate motives, although to modern eyes it looks innocuous.

· More debatable were the portraits taken of the young Alice Liddell and her siblings by the photographic pioneer and writer Charles Dodgson, now better known under his pseudonym, Lewis Carroll. Alice was also the inspiration for his masterpiece, Alice In Wonderland, and the nature of her relationship with Dodgson has long been subject of intense scholastic debate.

· In March 2001, the Saatchi gallery in north London was visited by police, who had been tipped off about the American artist Tierney Gearon's pictures of her children running naked on beaches and posing in masks. No charges were brought.